BothGame of Thronesand its prequel,House of the Dragonhave emphasized the Targaryen reliance on prophecies and dreams. Their faith in prophecies stems from the fact that they survived the Doom of Valyria by escaping well in time. Though the Targaryens were far from the most powerful Valyrian nobles, they survived because their the-then patriarch, Aenar had set sail to the island of Dragonstone, thanks to his daughter Daenys the Dreamer who had prophetic visions about the cataclysm. Aenar had safely moved his family, five dragons to the island of Dragonstone.
Anotherimportant event in Targaryen history, the Tragedy at Summerhall took place forty years before the events ofGame of Thrones. It rose out of the Targaryens' reliance on prophecies, dreams, and visions. The tragedy, as the name suggests, occurred at the lightly fortified Targaryen castle of Summerhall located in the Stormlands. The castle was used by Targaryen princes as their summer home and it was built by King Daeron II Targaryen. Summerhall eventually passed onto his son, Prince Maekar whose son, King Aegon V Targaryen aka Egg is central to the tragedy. His desire to restore dragons to the Seven Kingdoms culminated in the great fire that destroyed Summerhall.

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King Aegon V Targaryen’s Troublesome Reign
As a child, Prince Aegon V and his elder brother Prince Aemon dreamed of becoming dragonriders and hoped that their dragon eggs would somehow hatch. Aegon became king after Prince Aemon (portrayed by the late actor Peter Vaughan inGame of Thrones) ceded rule to him and chose to take the Wall. Aegon spent his reign quelling uprisings of various kinds, most notably the Fourth Blackfyre Rebellion. He loved the smallfolk and introduced a number of measures and reforms for the betterment. His measures angered the lords and without the dragons acting as a deterrent, he was forced to compromise with them on many issues.
King Aegon V was nostalgic for the Targaryen heydays and his House’s ownership of dragons. While he wanted to bring prosperity and justice for everyone in the realm, his reign was quite tumultuous. He faced open defiance from his children and they practically alienated House Targaryen by marrying who they wished. His oldest, Duncan abdicatedthe Iron Throneto marry a commoner named Jenny of Oldstones, his children Jaehaerys and Shaera fell in love and married whereas his youngest Daeron pursued a relationship with a Knight. Facing trouble on all ends, King Aegon V was this convinced that the only way to bring peace and prosperity to the realm was with dragons.

King Aegon attempted to hatch the last of the dragon eggs at Summerhall in 259 AC. He summoned his closest to celebrate the pregnancy of his granddaughter Rhaella. He took seven fossilized dragon eggs to honor the Seven Gods. Nine mages worked spells over the eggs, maesters poured over them and Baelor the Blessed prayed. The ritual involved pyromancers, and Aegon’s brother, Aerion who liked to dabble into the black arts drank wildfire believing it would transform him into a dragon. The fire got out of control and it turned into an inferno that engulfed Aegon, and by implication, Prince Duncan, Ser Duncan the Tall, and Maester Corso. It razed Summerhall to the ground thereby killing beloved Egg - one ofthe key members of House Targaryen.
Dragon Dreams And The Aftermath Of Summerhall
King Aegon V Targaryen ferociously believed in the return of dragons. He dreamed that the flying beasts would take over the skies of the Seven Kingdoms once again. He spent the last years of his rule in search of knowledge about dragon breeding. He even commissioned journeys as far as Asshai to find information on the ancient dragon breeding lore. His beliefs and efforts ultimately came to a head at Summerhall. Very few people survived the fire and far fewer among the survivors wanted to speak of the tragedy. Princess Rhaella Targaryen who came out alive gave birth toPrince Rhaegaramid the flames of Summerhall.
The Tragedy at Summerhall nearly diminished House Targaryen, and the remaining royals were later killed in Robert’s Rebellion. Daenerys and her brother Viserys were believed to be the last of the Targaryens at the beginning ofGame of Thrones. Maester Aemon Targaryen who served the Night’s Watch remained an exception until his death inGame of Thronesseason 5, episode 7, “The Gift.” He talked fondly about his little brother, Aegon and described him as a “jolly fellow” on his deathbed. Rhaegar and Lyanna Stark’s true-born son, Jon Snow whose character is up fora potential Jon Snowsequel series, served alongside Maester Aemon at the Wall. He is the last surviving Targaryen in the serialized canon.
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